[practice]String & File Ops
String Methods Deep Dive
# theory
essential methods
text = " Hello, World! "
text.strip() # "Hello, World!" - remove whitespace
text.lower() # " hello, world! "
text.upper() # " HELLO, WORLD! "
text.title() # " Hello, World! "
text.replace("World", "Python") # " Hello, Python! "
text.split(",") # [" Hello", " World! "]
"-".join(["a", "b", "c"]) # "a-b-c"checking content
"hello".startswith("he") # True
"hello".endswith("lo") # True
"hello".isalpha() # True (only letters)
"123".isdigit() # True (only digits)
"hello123".isalnum() # True (letters + digits)
"hello" in "hello world" # True (substring check)formatting & padding
"42".zfill(5) # "00042" - pad with zeros
"hi".ljust(10) # "hi " - left justify
"hi".rjust(10) # " hi" - right justify
"hi".center(10) # " hi " - center
# Format method
"{} is {}".format("Python", "fun")
"{name} is {age}".format(name="Alice", age=25)slicing
text = "Python"
text[0] # "P" - first character
text[-1] # "n" - last character
text[0:3] # "Pyt" - first 3
text[3:] # "hon" - from index 3 to end
text[::-1] # "nohtyP" - reversedfinding & counting
"hello world".find("world") # 6 (index where found)
"hello world".find("xyz") # -1 (not found)
"hello world".count("l") # 3 (occurrences)
"hello world".index("world") # 6 (like find, but errors if not found)# examples [3]
# example 01 · cleaning user input
Common pattern for processing user data
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# example 02 · formatting numbers
Pad and format numeric strings
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# example 03 · search and replace
Find and modify text content
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# challenges [2]
# challenge 01/02todo
Given phone = ' (555) 123-4567 ', extract just the digits and print them.
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# challenge 02/02todo
Split 'apple,banana,cherry' by comma and join with ' - ' between each. Print the result.
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# project
# project-challenge
thread: Sales Performance Dashboard · reward: 50 xp
# brief
The sales data has inconsistent SalesRep name formatting. Some names have extra spaces or inconsistent capitalization. Clean the names to ensure proper formatting for the dashboard display.
# task
Clean Sales Rep Names
# your code
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